1. Field of the Invention
The invention relates to a system and method for providing voice communication to subscribers over data networks.
2. Brief Description of the Related Art
Networks carry three types of information: voice, video, and data. Historically, these different forms of information have been transported over different networks. Specifically, the telephone network delivered voice information; private corporate networks delivered data information; and broadcast networks delivered video information. Each service was provided by a specific form of infrastructure—the telephone network used copper wires to reach subscribers, broadcast television used the airwaves, cable television used coaxial cable, and so forth.
With advances in technology, the different forms of information can now be carried by any delivery platform. For example, telephony services (i.e., voice and facsimile) can be transported over data networks, such as the Internet.
“Internet telephony” refers to the transfer of voice information using the Internet protocol (IP) of the TCP/IP or UDP/IP protocol suite. Internet telephony uses the Internet to simulate a telephone connection between two Internet users and to bypass the local exchange carriers' and inter-exchange carrier's telephone networks. Internet telephony works by converting voices into data which can be compressed and split into packets. These data packets are sent over the Internet like any other packets and reassembled as audio output at the receiving end. The ubiquitous nature of the Internet allows a user to complete such Internet telephone connections to many countries around the world. Accordingly, by using the Internet to provide telephony services, the user can avoid paying per-minute toll charges assessed by the user's local exchange carrier and/or inter-exchange carrier. Rather, the user is subject to only his or her local Internet connection fees. The result may be considerable savings when compared to international telephone rates.
In addition, the Internet utilizes “dynamic routing,” wherein data packets are routed using the best routing available for a packet at a particular moment in time, given the current traffic patterns. This system allows many different communications to be routed simultaneously over the same transmission facilities. In contrast, a circuit-switched telephone network, such as the public switched telephone network (PSTN), establishes dedicated, end-to-end transmission paths. Consequently, the Internet allows network resources to be used more efficiently.
Most existing dial-up systems require both parties to be connected to the Internet through a multimedia personal computer to establish an Internet telephone call. As shown in FIG. 1, the multimedia personal computers, which have been loaded with certain telephony software, can access the data network using a local circuit-switched telephone network to a voice over packet gateway residing in an Internet Service Provider (ISP) point of presence.
The typical multimedia personal computer system used for Internet telephony includes a personal computer, a monitor, an analog-voice-to-digital-signal and digital-signal-to-analog-voice converter (converter), Internet telephone software, a full-duplex sound card, a microphone, speakers, and a 28 Kbps or higher rate modulation/demodulation (modem) device. As such, the multimedia personal computer system includes several components or devices and is not easily portable, which may be undesirable for travelling business people. Further, such a personal computer system may be expensive to set up and maintain.
Accordingly, it would be desirable to provide a method and system for voice communication over a data network that addresses the drawbacks of known systems.